Yarn tensioning means

ABSTRACT

A yarn storage drum is provided with a separate external support for holding a plurality of yarn tension rings in selectively spaced, stacked relation. Each ring includes spacer means for supporting a next-above ring. Each ring has an annular set of elongated fingers which project from the base of the ring and incline toward the storage drum and also circumferentially thereto. The fingers of the lower rings overlap those of the upper rings, and the tips of the two fingers of each ring contact the periphery of the drum and together apply a selected uniform tension to the yarn. The tension rings are free to float transversely with respect to the drum.

States Patent Lawson et a1,

[ YARN TENSIONING MEANS 3,648,939 3/1972 ROSen 242/4701 3,702,17611/1972 242/47.0l [75] lnvemors' John Provldence, 3,759,300 9/1973Pfarrwaller 242/4701 Charles Cooper, Attleboro, Mass- 3,791,598 2/1974Vischiani et a1. 242/4712 [73] Assignee: Lawson-Hemphill, Inc., CentralF ll R1 Primary Examiner-Stanley N. Gllreath Filed p 18 1974 Attorney,Agent, or FirmMiller, Frailey & Prestia [21] Appl. No.: 461,909 [57]-ABSTRACT R l d [13 A li i D A yarn storage drum is provided with aseparate exter- [63] Continuation-in-part of S61. NO. 431 478 Jan. 7 Pfor holding a plurality yam m 1974 1n selectlvely spaced, stackedrelation. Each ring includes spacer means for supporting a next-abovering. 52 US. Cl. 242/4701; 242/4712; 242/128; 521811 g has an annularSet of elqngated fi s 242/147 R wh1ch pro ect from the base of the ringand incline 51 1111. (:1. B65H 51/20; B65H 59/00 toward the Storage drumand also Circumferentially 5 Field f Search 242 47 7 128, R thereto. Thefingers of the lower rings overlap those of the upper rings, and thetips of the two fingers of each 5 References Cited ring contact theperiphery of the drum and together UNITED STATES PATENTS apply aselected uniform tension to the yarn. The tension rings are free tofloat transversely with respect to 3,411,548 11/1968 Pfarrwaller242/47.12 X the drum. 3,490,710 1/1970 Muhlhausler 242/4701 4 Claims, 6Drawing Figures l8 Y\,: If r 12 1 Z 25 if US. Patent D56. 16, 1975 Sheet1 of2 3,926,381

f 26 L Y :\\I if 2 US. Patent Dec. 16, 1975 Sheet 2 of2 3,926,381

YARN TENSIONING MEANS CROSS REFERENCE TO OTHER APPLICATIONS Thisapplication is a continuation-in-part of our pending patent applicationSer. No. 431,478, filed Jan. 7, 1974, entitled Yarn Tensioning Device.

BACKGROUND OF THE INVENTION This invention concerns yarn storage devicesof the type wherein a drum, which may either be rotational or fixed,takes up yarn from a yarn package for delivery to a yarn consumingmachine. The yarn is wound tangentially on the drum, usuallyintermittently, and is pulled continuously therefrom axially through atensioning ring which encircles the drum and which applies a drag ortension to the yarn.

The invention relates specifically to yarn storage devices of the typewherein the tensioning rings consist of a base ring from which extend aplurality of elongated fingers at regularly spaced intervals. Thefingers project along lines which incline toward the axis of the storagedrum and also extend circumferentially thereto. The distal ends of thefingers rest against the surface of the drum.

Tension rings for the purpose of applying tension or drag to yarn beingpulled from a yarn package or other yarn storage means or device arewell known in the art. See, for example, US. Patents to Chapman US. Pat.No. 350,345, Grothey US Pat. No. 2,366,101, Gift US. Pat. No. 2,838,922,Sarfati et al. US. Pat. No. 3,225,446, Rosen US. Pat. No. 3,648,939 andRosen US. Pat. No. 3,702,176; and British Pat. Nos. 12,321 (1885) and6727 (1892).

SUMMARY OF THE INVENTION A principal object of the present invention isto provide improved tension means for yarn storage devices of the typereferred to hereinabove.

The object of the invention is achieved by providing a separate supportexterior of the yarn storage drum for supporting at least one tensionring in an encircling position about the drum and at a spaced distancetherefrom. This arrangement avoids the annular shoulder on the drum usedby some of the prior art devices to support the tension ring on thedrum, and thereby reduces the angle of contact of the yarn with thetake-off yarn guide which is spaced from the drum on the projected axisthereof. Reducing this angle of contact provides a smoother yarn travelor flow to the yarn consuming machine.

The further object of the invention is to provide a plurality of tensionrings, stacked one above the other, at such axially spaced separationsthat the fingers of each lower ring overlap those of the next above ringwithout any contact between the fingers of the upper and lower rings,whereby yarn pulled from the storage drum is selectively andcontrollably tensioned by the fingers of each of the axially stackedtension rings.

It is common practice with tension rings of similar design, such asshown in Rosen v US. Pat. No. 3,702,176, to stack multiple rings toachieve higher tensions without regard to the axial relation of therings. However, such stacking leads to unpredictable and uncontrollabletensions. For, when tension rings are stacked so as to causeinterference between the fingers of one ring and another, the flexingability of the fingers of one ring is affected by the pressure of thefingers of the other ring, and the resulting tension on the yarn is nota simple addition of the effect of the two rings. It is, therefore, afurther object of this invention to provide a tension ring designwhereby rings may be stacked to achieve increased tensions wherein eachadditional ring adds only that increase in tension which it is designedto add, that is, each additional ring adds only that tension it alonewould provide in the absence of other rings.

Further, it has been demonstrated that, when higher yarn tensions arerequired, a more uniform, smoother tension is achieved through the useof multiple light tension rings rather than from using a single stifferor more rigid ring designed to produce the same total tension. This isbecause the stronger fingers of such a single ring tend to pluck theyarn and produce a bumpy yarn flow. The smaller the drag of each fingeron a yarn the less the pluck effect. Thus, where two or three times asmany fingers can be used to produce a selected tension, the smootherwill be the yarn flow.

Additionally, it should be noted that an increase in bulk of a yarn,such as a knot or slub, will pass under multiple sets of light,easily-flexed fingers much more smoothly than it will pass under asingle set of relatively stiff fingers.

In the preferred arrangement, the lowermost tension ring rests looselyon an external support ring, and each succeeding tension ring stackedabove it rests loosely on the next lower ring. This arrangement permitseach tension ring to float in the transverse plane of its base ring,with respect to the yarn storage drum. Thus, each tension ring is freeto move radially, in the transverse plane of its base ring, until theopposing arcuate forces exerted by its fingers on the periphery of thestorage drum are substantially in balance. By reason of this freedom tofloat radially, or transversely, with respect to the storage drum, thedistal ends of the fingers of each tensioning ring exert a highlyuniform tension or drag on the yarn, as it is withdrawn from the drum.

As a result of this capacity of the rings to float, and thereby seek anequilibrium condition of substantially uniform finger pressurecircumferentially about the drum, compensation is provided automaticallyfor slight but routine defects, such as molding errors in the fingers ofthe tension ring, axial misalignment of the parts, e.g. between thestorage drum and the ring support, and run-out or wobble conditionsoccurring between the periphery of the storage drum and the tension ringsupport arising, for example, from defects in the drum or its supportingshaft.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevational view, partlyin section, of the lower portion of a known form of yarn storage devicehaving thereon two tensioning rings supported in accordance with thepresent invention;

FIG. 2 is a view looking along the line 22 of FIG. 1;

FIG. 3 is a plan view of one form of tensioning ring provided inaccordance with the present invention;

FIG. 4 is a view in section along the line 44 of FIG.

FIG. 5 is a plan view of another form of tensioning ring in accordancewith the present invention;

FIG. 6 is a view in section along the line 66 of FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 there isshown, largely in section, the lower portion of a known form of yarnstorage feeder having a stationary drum which receives yarn tangentiallyfrom a yarn package (not shown) and about which the yarn Y is collected.A storage feeder of the type shown partially in FIG. 1 is shown indetail in John B. Lawson US. Pat. No. 3,776,480, issued Dec. 4, 1973,entitled Yam Handling Apparatus.

In some forms of storage devices, the yarn collecting drum 10 isrotatable. So far as the present invention is concerned, the drum may beeither stationary or rotatable. However, in the particular formillustrated in FIG. 1, the yarn collecting drum 10 is stationary and theyarn Y is wound thereabove by a rotatable yarn guide (not shown) whichis revolvable about the drum. For such a rotatable yarn guide, see theaforesaid US. Pat. No. 3,776,480.

As yarn Y on the storage drum 10 is pulled downwardly to theyam-consuming equipment (not shown) it leaves the peripheral surface ofthe yarn storage drum 10 and passes through a stationary yarn guide 16supported by a channel bracket 17. Yarn guide 16 is located below theyarn collecting drum 10 on the projected center axis thereof. Stationarybracket 17 is supported at its upper end from the frame of the device.

In accordance with the present invention, stationary bracket 17 supportsa ring 20 in such a position that it encircles drum 10 near the lowerend thereof. Ring 20 may preferably be metal and may consist of acircular loop from which a pair of arms 21 extend radially outwardly.The ends of the radial arms 21 are supported in a pin 22 which extendsacross the channel of bracket 17 and is supported in the sidewallsthereof. The pin 22 may be provided with a locking detent fastened tobracket 17 or other means which allows the ring 20 to be adjusted intoposition by pivotal movement about pin 22 so that ring 20 may be swungdown to load tension rings 25 onto it. The particular means justdescribed for securing ring 20 pivotally to bracket 17 is not importantto the present invention. Any suitable means may be used. It isimportant, however, that the ring 20 be supported by a bracket or othermeans spaced radially outwardly from the drum l0, and that such means becapable of supporting the loop or ring 20 in an encircling positionabout drum 10 at a small, spaced distance therefrom, as seen in FIG. 1.

In accordance with a preferred embodiment of the present invention, thering 20 is used to support one or more yarn tension rings 25. Thetension rings 25, preferably plastic, are provided integrally withspacer means so that they can be stacked one above the other atselected, axially spaced locations.

Each of the tension rings 25 may be identical to the other. In apreferred form, illustrated in FIGS. 3 and 4, each ring 25 has anannular base portion or ring 26 which is provided with an integralannular rib 28. Rib 28 performs two functions. One, it stiffens theannular base portion 26. Two, it functions as a spacer, as will bedescribed.

From the inner rim of each ring 25 an annular set of elongated fingers27 and 127 extend downwardly and inwardly. These fingers may preferablybe at regular spaced locations leaving interstices between the fingers.The fingers are inclined inwardly toward the axis 4 0f the ring, as seenin FIG. 4. They also extend in the circumferential direction, as seen inFIG. 3.

The height of rib 28 is chosen to provide the desired axial spacingbetween the lower and upper rings 25 and their fingers 27 and 127, sothat the fingers of the two rings are in overlapping relation, but notcontacting, as seen in FIGS. 1-4, with the tips of the fingers of thetwo rings resting on the surface of the drum 10. While the two tensionrings 25 will usually be identical, the component parts of the upper andlower rings are distinguished by reference numerals which differ by 100.For example, in FIG. 2, the fingers of the upper ring are 27; thefingers of the lower ring are 127.

While only two tension rings 25 are shown in FIGS. 1-4, the presentinvention contemplates that more than two may be used, and in FIGS. 5and 6, three tension rings are illustrated. In addition, FIGS. 5 and 6illustrate another form of tension ring, in which the spacer means, inlieu of the annular rib 28 shown in FIGS. 3 and 4, consists of aplurality of posts 29, three being shown at spacing. The number of posts29 may, of course, be greater than three. The form of spacer shown inFIGS. 5 and 6 is not, however, presently preferred since the stiffeningeffect of the rib 28 is lost.

The lowermost tension ring 25 rests loosely on the support ring 20. Thisarrangement permits yarn tension ring 25 to float radially, in thetransverse plane of its base ring or portion 26, with respect to theyarn storage drum 10. Thus, tension ring 25 is free to move radially inthe transverse plane of its base ring, until the opposing arcuate forcesexerted by its fingers on the surface of the storage drum 10 aresubstantially in balance.

Similarly, each of the succeeding, axially stacked yarn tension rings 25is supported loosely on the annular rib 28 of the ring 25 next below it.Thus, each of the upper yarn tension rings 25 also is free to float inthe transverse plane of its base ring 26, until it finds a position ofequilibrium, in which its fingers exert a substantially uniform pressurecircumferentially about the drum.

This capacity of the individual yarn tension rings 25 to float, untilthey adjust themselves to a position of exerting substantially equalfinger pressure about the storage drum, serves to compensateautomatically for minor defects of alignment or construction in theaxially disposed parts of the yarn storage feeder. It also serves toenhance the uniformity of the tension exerted by the tension rings onthe yarn.

The tension ring means shown and described in the present applicationhas other advantages over prior art devices. Since no shoulder isrequired on the drum surface below the tension ring 25 to support thering, the yarn slides down along the drum surface to the centrallylocated yarn guide 16 along a path which provides a reduced angle ofcontact with the guide, thereby providing a smoother yarn path. This is,of course, advantageous. This advantage is obtained whether or not twoor more tension rings are used.

Further, since the yarn tension rings 25 are supported about the storagedrum 10 by the separate, external support ring 20, the tendency of theyarn tension rings 25 to fall off the drum is, for all practicalpurposes, eliminated. One of the difficulties with the prior artdevices, which utilize an annular shoulder on the storage drum tosupport the yarn tension rings, is the tendency for the rings to beknocked off of the drum when they are disturbed or jarred by knots orslubs or similar imperfections in the yarn passing under the tensionring as it is withdrawn from the drum.

Another advantage arises from the employment of two or more tenstionrings 25, stacked one above the other, in such relative positions thatthe fingers of one ring do not contact the fingers of another ring. Asthe yarn leaves the drum 10, a separate drag is applied thereto by eachset of axially spaced fingers. Thus, additional drag may be added byadding additional tension rings. The two or more tenstion rings are freeto move angularly, as well as radially, relative to the drum and alsorelative to each other. In operation, as the yarn is pulled past thetips of the fingers of the two or more sets of fingers, the rings willmove or float relative to each other until the most uniform tensionpossible is applied to the yarn. Thus, the present invention, by usingtwo or more sets of tension rings applies a more even tension, ascompared with that provided by prior art devices.

What is claimed is:

l. A yarn tension ring for a yarn storing device having a yarn storagedrum, said tension ring including:

a. a base ring for surrounding the storage drum,

b. a plurality of bristle-like flexible elements extending from the basering axially beyond the base ring and inwardly toward the axis of thering, whereby the tips of the flexible elements are contiguous with thesurface of the drum when the tension ring is mounted relative thereto,and

c. means for locating a second yarn tensioning ring surrounding thestorage drum at a selected, axially spaced, distance from said tensionring to space the tips of the flexible elements of of a second yarntension ring from the tips of the flexible elements of said tension ringa distance sufficient to avoid contact between the respective flexibleelements of said tension ring and a second ring,

(1. said locating means comprising spacer means mounted on the base ringand extending from the base ring in a direction generally opposed to thedirection toward which the flexible elements extend from the base ring.

2. A tension ring according to claim 1, wherein the spacer meanscomprises an annular rib integral with the base ring of the tensionring.

3. A tension ring according to claim 1, wherein the spacer meanscomprises a plurality of spaced, generally annularly-arranged,protuberances formed integrally with the base ring of the tension ring.

4. Yarn tensioning means for a yarn storing device having a yarn storagedrum, said tensioning means comprising a. a plurality of axially stackedyarn tension rings surrounding the drum,

b. each tension ring comprising a base ring and a plurality ofbristle-like flexible elements extending from the base ring axiallybeyond the base ring and inwardly toward the axis of the ring, wherebythe tips of the flexible elements are contiguous with the surface of thedrum when the tension ring is mounted relative thereto, and

c. means for locating the plurality of tension rings at spaced intervalsaxially of the storage drum with the tips of the flexible elements ofeach ring spaced axially from the tips of the flexible elements of eachnext adjacent ring a distance sufficient to avoid contact between therespective flexible elements of said adjacent rings,

d. said locating means comprising i. a support ring disposed externallyof the drum for supporting the stack of yarn tension rings, and ii.spacer means mounted on the base ring of each yarn tension ring andextending from the base ring in a direction generally opposed to thedirection toward which the flexible elements extend

1. A yarn tension ring for a yarn storing device having a yarn storagedrum, said tension ring including: a. a base ring for surrounding thestorage drum, b. a plurality of bristle-like flexible elements extendingfrom the base ring axially beyond the base ring and inwardly toward theaxis of the ring, whereby the tips of the flexible elements arecontiguous with the surface of the drum when the tension ring is mountedrelative thereto, and c. means for locating a second yarn tensioningring surrounding the storage drum at a selected, axially spaced,distance from said tension ring to space the tips of the flexibleelements of of a second yarn tension ring from the tips of the flexibleelements of said tension ring a distance sufficient to avoid contactbetween the respective flexible elements of said tension ring and asecond ring, d. said locating means comprising spacer means mounted onthe base ring and extending from the base ring in a direction generallyopposed to the direction toward which the flexible elements extend fromthe base ring.
 2. A tension ring according to claim 1, wherein thespacer means comprises an annular rib integral with the base ring of thetension ring.
 3. A tension ring according to claim 1, wherein the spacermeans comprises a plurality of spaced, generally annularly-arranged,protuberances formed integrally with the base ring of the tension ring.4. Yarn tensioning means for a yarn storing device having a yarn storagedrum, said tensioning means comprising a. a plurality of axially stackedyarn tension rings surrounding the drum, b. each tension ring comprisinga base ring and a plurality of bristle-like flexible elements extendingfrom the base ring axially beyond the base ring and inwardly toward theaxis of the ring, whereby the tips of the flexible elements arecontiguous with the surface of the drum when the tension ring is mountedrelative thereto, and c. means for locating the plurality of tensionrings at spaced intervals axially of the storage drum with the tips ofthe flexible elements of each ring spaced axially from the tips of theflexible elements of each next adjacent ring a distance sufficient toavoid contact between the respective flexible elements of said adjacentrings, d. said locating means comprising i. a support ring disposedexternally of the drum for supporting the stack of yarn tension rings,and ii. spacer means mounted on the base ring of each yarn tension ringand extending from the base ring in a direction generally opposed to thedirection toward which the flexible elements extend from the base ring.